Array substrate, display device and driving method thereof

ABSTRACT

The invention provides an array substrate, a display device and a driving method thereof. The array substrate comprises a plurality of gate lines and data lines, the gate lines and the data lines define a plurality of pixel units arranged in an array, each of which comprises a common electrode and a pixel electrode, wherein the common electrodes of at least part of the pixel units are formed as touch driving electrodes, at least part of the data lines are formed as touch sensing electrodes, wherein the touch driving electrodes and the touch sensing electrodes are insulated from each other; the touch driving electrodes are applied with common voltages during a display period, and are applied with touch scan signals during a touch period; and the touch sensing electrodes are applied with data signals during the display period, and generate and output coupling signals during the touch period.

FIELD OF THE INVENTION

The invention relates to the field of liquid crystal display technology,and particular to an array substrate, a display device and a drivingmethod thereof.

BACKGROUND OF THE INVENTION

Liquid crystal display screens have been widely used in various displayfields, such as family, public places, offices and personal electronicproducts etc. Generally, a liquid crystal display screen consists of aliquid crystal cell formed by aligning an array substrate and a colorfilter substrate, a polarizer and a backlight module etc. With theincrease of people's demand on display, currently, the liquid crystaldisplay screen with a touch screen has been more and more widely used,the touch screen typically includes a resistive, capacitive, optical,acoustic touch screen or the like, as an in-cell capacitive touch screenis formed by providing a touch sensing circuit in the cell, thereforethe cell may be thinner and lighter compared to other touch screens, andthus the cost is decreased, and the touch screen with such a structuregets more and more attention.

FIG. 1 is a principle diagram of a common in-cell capacitive touchscreen, it can be seen from the figure that, the touch screen is formedwith a large number of metal wires crossing with each other inhorizontal and vertical directions, wherein the metal wires inhorizontal direction may be used as signal lines for transmittingsensing touch signals and indicated by T1, T2, T3 , . . . , TNrespectively, and signal lines for receiving the sensing touch signalsmay be indicated by R1, R2, R3, . . . , RN respectively. When the touchscreen is touched, a corresponding received signal is changed so thatthe location of the touch may be positioned, and then the touch may beprocesses by a touch unit.

However, in manufacturing the above in-cell capacitive touch screen, itis necessary to fabricate a large number of metal lines separately assignal lines for touch so that the process is complicated, and in themeanwhile, the aperture ratio of the display is decreased.

SUMMARY OF THE INVENTION

In view of above problem, the present invention provides an arraysubstrate, a display device and a driving method thereof, which cansolve the above problem.

A solution to solve the above problem is an array substrate, whichcomprises a plurality of gate lines and a plurality of data lines, thegate lines and the data lines define a plurality of pixel units arrangedin an array, each of which comprises a common electrode and a pixelelectrode, wherein

the common electrodes of at least part of the pixel units are formed astouch driving electrodes, at least part of the data lines are formed astouch sensing electrodes, and the touch driving electrodes and the touchsensing electrodes are insulated from each other;

the touch driving electrodes are applied with common voltages during adisplay period, and are applied with touch scan signals during a touchperiod; and

the touch sensing electrodes are applied with data signals during thedisplay period, and generate and output coupling signals during thetouch period.

In the array substrate in the invention, in the display period, datasignals are applied to data lines, at this time, the pixel electrodesare driven by the data lines, that is to say, the touch sensingelectrodes are applied with data signals during the display period.Meanwhile, common voltages are applied, in the display period, to thecommon electrodes, wherein the common electrodes maintain a uniformcommon voltage, and at this time, the touch driving electrodes areapplied with the common voltages. In the touch period, the touch drivingelectrodes are applied with touch scan signals, the touch sensingelectrodes generate and output coupling signals to a judging unit, thenthe judging unit determines the location of the touch point based on thecoupling signals output from the touch sensing electrodes so as toachieve a touch display.

Preferably, the common electrodes of the pixel units in every two to sixrows are connected as one touch driving electrode.

Preferably, the touch driving electrodes are connected in a rowdirection or a column direction of the pixel units.

Preferably, the array substrate further comprises common electrodelines, and the touch driving electrodes are connected in the rowdirection or the column direction of the pixel units through the commonelectrode lines.

Preferably, the pixel electrode is provided above the common electrode,and is a slit-shaped electrode.

Preferably, both of the pixel electrode and the common electrode areslit-shaped electrodes.

Preferably, each of the pixel units comprises a thin film transistor, agate of which is connected to the gate line, a source of which isconnected to the data line, and a drain of which is connected to thepixel electrode.

A solution to solve the above problem is a display device comprising theabove array substrate.

Since the display device in the invention comprises the above arraysubstrate, it can achieve the touch function.

A solution to solve the above problem is a driving method of a displaydevice, comprising:

dividing a time period for displaying one frame by the display deviceinto a display period and a touch period, wherein the display devicecomprises an array substrate, the array substrate comprises a pluralityof gate lines and a plurality of data lines, the gate lines and the datalines define a plurality of pixel units arranged in an array, each ofwhich comprises a common electrode and a pixel electrode, the commonelectrodes of at least part of the pixel units are formed as touchdriving electrodes, and at least part of the data lines are formed astouch sensing electrodes,

in the display period, sequentially applying gate scan signals to theplurality of gate lines, applying data signals to the plurality of datalines, and applying common voltage signals to the common electrodes; and

in the touch period, applying touch scan signals to the touch drivingelectrodes, the touch sensing electrodes couple the touch scan signalsand output coupling signals, and no signal is inputted into theplurality of gate lines.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a principle diagram for realizing touch function in the priorart;

FIG. 2 is structural diagram of an array substrate in embodiment 1 ofthe invention; and

FIG. 3 is a timing chart of a driving method of a display device inembodiment 3 of the invention.

Reference Signs

1. common electrode line; 2. data line; 3. gate line; 4. thin filmtransistor; 5. common electrode; and 6. pixel electrode.

DETAILED DESCRIPTION OF EMBODIMENTS

In order to make a person skilled in the art understand the solution ofthe invention better, the invention will be described in detail below inconjunction with drawings and embodiments.

Embodiment 1

As shown in FIG. 2, this embodiment provides an array substratecomprising a plurality of pixel units arranged in an array and definedby a plurality of gate lines 3 and a plurality of data lines 2, and eachof the pixel units comprises a common electrode 5 and a pixel electrode6. The common electrodes of at least part of the pixel units are formedas touch driving electrodes, at least part of the data lines 2 areformed as touch sensing electrodes, and the touch driving electrodes andthe touch sensing electrodes are insulated from each other. It should benoted that, in order to facilitate the description, only one gate line 3and one data line 2 are shown in FIG. 2, but the numbers of the gatelines and the data lines are not limited thereto.

The touch driving electrodes are applied with a common voltage during adisplay period, and are applied with touch scan signals during a touchperiod; and

the touch sensing electrodes are applied with data signals during thedisplay period, and couple the touch scan signals and output couplingsignals during the touch period.

In the array substrate of the embodiment, during the display period, thedata line 2 is applied with a data signal, and the pixel electrode isapplied with the data signal through the data line 2; at the same time,during the display period, the common electrodes 5 are applied withcommon voltages and the common electrodes 5 maintain a uniform commonvoltage. During the touch period, part or all of the common electrodes 5function as touch driving electrodes, which are applied with touch scansignals, and other common electrodes 5 which do not function as touchdriving electrodes are not applied with signals, at this time the touchsensing electrodes couple the touch scan signals and output them to ajudging unit, then the judging unit determines a location of thetouching point according to the signals coupled by the touch sensingelectrodes, so that a touching function may be achieved.

In realizing the touch function, common electrodes 5 of the pixel unitsin each row may be connected to function as a touch driving electrodeduring the touch period, alternatively, common electrodes 5 of the pixelunits in a plurality of rows may be connected to function as a touchdriving electrode during the touch period. In order to simplify thetouch driving without decreasing the touch accuracy, preferably, thecommon electrodes 5 of the pixel units in adjacent two to six rows areconnected as a touch driving electrode.

In order to simplify the wiring and save cost, preferably, the touchdriving electrodes are connected in a row direction or a columndirection of the pixel units.

Preferably, the array substrate further comprises common electrode lines1, and the touch driving electrodes are connected in the row directionor the column direction of the pixel units through the common electrodelines 1. Of course, the common electrodes 5 are not limited to beconnected through the common electrode lines 1, it is possible to useother metal wires. Alternatively, it is also possible to connect thecommon electrodes 5 of adjacent pixel units using the same material asthe common electrodes 5 to form the touch driving electrodes when thecommon electrodes 5 are manufactured.

Preferably, the array substrate may be of ADS mode. At this time, thepixel electrode 6 is provided above the common electrode 5 and is aslit-shaped electrode, the common electrode 5 is a plate-shapedelectrode, the pixel electrode 6 and the common electrode 5 areseparated from each other through an insulating planarization layer. Ofcourse, it is also possible to provide the common electrode 5 above thepixel electrode 6, at this time, the common electrode 5 is a slit-shapedelectrode, and the pixel electrode 6 is a plate-shaped electrode. Ofcourse, both of the pixel electrode 6 and the common electrode 5 may beslit-shaped electrodes and are provided to be insulated from each other,wherein the positions of the pixel electrode 6 and the common electrode5 may be exchanged.

Preferably, both of the pixel electrode 6 and the common electrode 5 maybe slit-shaped electrodes, and are provided in the same layer andinsulated from each other, and at this time, the array substrate is ofIPS mode.

It should be noted that, this embodiment is not limited to the arraysubstrate of ADS and IPS modes. The common electrodes and the pixelelectrodes may be made of Indium gallium zinc oxide (IGZO), Indium zincoxide (IZO), indium tin oxide (InSnO), indium gallium tin oxide(InGaSnO) or the like, and furthermore, they may be made of othertransparent conductive materials.

Preferably, the pixel unit further comprises a thin film transistor 4, agate of which is connected to the gate line 3, a source of which isconnected to the data line 2, and a drain of which is connected to thepixel electrode 6. When the gate line 3 is at a high level, the thinfilm transistor 4 is turned on, the data line 2 is connected to thepixel electrode through the thin film transistor 4 to write a pixelvoltage into the pixel electrode 6, and the common electrode 5 isapplied with a common voltage signal. When the gate line 3 is at a lowlevel, the thin film transistor 4 is turned off, electrode bars in thecommon electrodes 5 functioning as touch driving electrodes are appliedwith touch scan signals, specifically, the driving signal may betransferred through the common electrode line 1.

In the array substrate in the embodiment, at least part of the commonelectrodes 5 are used as touch driving electrodes, and at least part ofthe data lines 2 are used as touch sensing electrodes. When a touchoccurs, the coupling capacitance between the touch driving electrode andthe touch sensing electrode is changed, resulting in change in acoupling signal output from the touch sensing electrode, so that aposition touched may be determined. A display panel may have touchdisplay function by applying the array substrate to the display panel.

Embodiment 2

This embodiment provides a display device comprising the array substratein the embodiment 1. The display device may be: any product or componentwith a display function, such as a mobile phone, a tablet computer, atelevision, a display, a notebook computer, a digital photo frame and anavigator.

Since the display device of the embodiment has the array substrate inembodiment 1, it can have a touch function.

Of course, the display device of the embodiment may also comprise otherconventional structures, such as a power supply unit, a display drivingunit etc.

Embodiment 3

The embodiment provides a driving method of a display device, whichcomprises:

dividing a time period for displaying one frame by the display deviceinto a display period and a touch period, wherein the display devicecomprises an array substrate, the array substrate comprises a pluralityof gate lines 3 and a plurality of data lines 2, the gate lines 3 andthe data lines 2 define a plurality of pixel units arranged in an array,each of which comprises a common electrode 5 and a pixel electrode 6,the common electrodes 5 comprise touch driving electrodes, and the datalines 2 comprise touch sensing electrodes. It should be noted that, inorder to facilitate the description, FIG. 2 only shows a gate line 3 anda data line 2, but numbers thereof are not limited thereto.

In the display period, sequentially applying gate scan signals to theplurality of gate lines 3, applying data signals to the plurality ofdata lines 2, and applying common voltage signals to the commonelectrodes 5, so that the pixel units are driven to display.

In the touch period, applying touch scan signals to the touch drivingelectrodes, the touch sensing electrodes couple the touch scan signalsand output coupling signals, and no signal is inputted into a controllerfrom the gate lines 3, then the controller may determine the touchcoordinates according to changes in amount of charges, so that touchdisplay may be realized.

In order to understand the display method of the embodiment better, anexample will be described below.

FIG. 3 shows an operation timing chart of the above display device, andas shown in FIG. 3, the display device operates in a time-divisionmanner. FIG. 3 shows an operation process of the display device in anoperation period for a frame of image (for example, a refresh frequencyis 60 Hz), wherein whether the display device is in a display period ora touch period is controlled by a signal (Vsync) applied to the gateline 3. In FIG. 3, in the prior 12.67 ms, the Vsync is at a high level,and the display is in the display period, and in the later 4 ms, theVsync is at a low level, and the display is in the touch period. Duringthe display period, the gate lines 3 control TFTs row-by-row to turn on,as shown by G1, G2, G3, . . . , Gn in FIG. 3, at this time, data signalsfor a corresponding picture are written into the data lines 2,meanwhile, uniform common voltage signals are inputted into the commonelectrode lines 1 through the driving unit, so that all of the commonelectrodes 5 maintain a certain voltage (signals on the commonelectrodes 5 and signals applied to the common electrode lines 1 are thesame), then the display device displays normally. During the touchperiod, the gate lines 3 are all at a low level, then all the switchunits (for example, thin film transistors 4) are turned off, electriccharges are maintained in the pixels, part or all of the commonelectrodes 5 functioning as the touch driving electrodes are appliedwith touch scan signals, at this time, part or all of the data lines 2functioning as the touch sensing electrodes generate and output couplingsignals, when a touch occurs, the coupling signal output from the touchsensing electrode is changed, so that the touched position may bedetermined.

It should be understood that, the above embodiments are described onlyto illustrate the principle of the invention, and the invention is notlimited thereto. Persons skilled in the art can make variousmodifications and improvements without departing from the principle andsubstance of the invention, and these modifications and improvementsshould be considered to be within the protection scope of the invention.

1-9. (canceled)
 10. An array substrate comprising a plurality of gatelines and a plurality of data lines, the gate lines and the data linesdefine a plurality of pixel units arranged in an array, each of whichcomprises a common electrode and a pixel electrode, wherein the commonelectrodes of at least part of the pixel units are formed as touchdriving electrodes, at least part of the data lines are formed as touchsensing electrodes, and the touch driving electrodes and the touchsensing electrodes are insulated from each other; the touch drivingelectrodes are applied with common voltages during a display period, andare applied with touch scan signals during a touch period; and the touchsensing electrodes are applied with data signals during the displayperiod, and generate and output coupling signals during the touchperiod.
 11. The array substrate of claim 10, wherein the commonelectrodes of the pixel units in every two to six rows are connected asa touch driving electrode.
 12. The array substrate of claim 10, whereinthe touch driving electrodes are connected in a row direction or acolumn direction of the pixel units.
 13. The array substrate of claim10, further comprises common electrode lines, wherein the touch drivingelectrodes are connected in the row direction or the column direction ofthe pixel units through the common electrode lines.
 14. The arraysubstrate of claim 10, wherein the pixel electrode is provided above thecommon electrode, and is a slit-shaped electrode.
 15. The arraysubstrate of claim 11, wherein the pixel electrode is provided above thecommon electrode, and is a slit-shaped electrode.
 16. The arraysubstrate of claim 12, wherein the pixel electrode is provided above thecommon electrode, and is a slit-shaped electrode.
 17. The arraysubstrate of claim 13, wherein the pixel electrode is provided above thecommon electrode, and is a slit-shaped electrode.
 18. The arraysubstrate of claim 10, wherein both of the pixel electrode and thecommon electrode are slit-shaped electrodes.
 19. The array substrate ofclaim 11, wherein both of the pixel electrode and the common electrodeare slit-shaped electrodes.
 20. The array substrate of claim 12, whereinboth of the pixel electrode and the common electrode are slit-shapedelectrodes.
 21. The array substrate of claim 13, wherein both of thepixel electrode and the common electrode are slit-shaped electrodes. 22.The array substrate of claim 10, wherein each of the pixel unitscomprises a thin film transistor, a gate of which is connected to thegate line, a source of which is connected to the data line, and a drainof which is connected to the pixel electrode.
 23. A display devicecomprising the array substrate of claim
 10. 24. A driving method of adisplay device, comprising: dividing a time period for displaying oneframe by the display device into a display period and a touch period,wherein the display device comprises an array substrate, the arraysubstrate comprises a plurality of gate lines and a plurality of datalines, the gate lines and the data lines define a plurality of pixelunits arranged in an array, each of which comprises a common electrodeand a pixel electrode, the common electrodes of at least part of thepixel units are formed as touch driving electrodes, and at least part ofthe data lines are formed as touch sensing electrodes, in the displayperiod, sequentially applying gate scan signals to the plurality of gatelines, applying data signals to the plurality of data lines, andapplying common voltage signals to the common electrodes; and in thetouch period, applying touch scan signals to the touch drivingelectrodes, and coupling the touch scan signals and outputting couplingsignals by the touch sensing electrodes, wherein no signal is inputtedinto the plurality of gate lines.